$colMain: #f00;
.payway{
    .btn-groups{
        .weui-btn{display: inline-block;margin-left: 30px;width: 210px;margin-top: 20px;}
        .weui-btn:nth-child(3n+1){margin-left: 0}
        .weui-btn.active{color: $colMain;border-color: $colMain}
    }
}